While doing performance analysis using Nividia Nsight I have found out that calls to SwapBuffers might start to block. I manage to reproduce the same behavior in a small test program by simulate slow CPU frames using a 6ms delay. After around 200 frames one can see that SwapBuffers starts to block almost like OpenGL switches mode in to a more strict synchronization. After 250 frames the 6ms delay is removed but SwapBuffers continues to block and never returns to the normal mode. Is this a feature in OpenGL trying to be smart and produce a smoother visualization?
Tested on Windows 10 and Geforce GTX 980.
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